An earlier air temperature monitor was patented in 1992 by David M. Bergstein (the present inventor) which, after testing, exhibited an error of about two (2) degrees F., maximum. This is described in U.S. Pat. No. 5,141,332, which issued on Aug. 25, 1992.
A publication by J. Y. Wang and C. M. M. Felton discusses temperature monitors, titled, “Instruments for Physical Environmental Measurements,” published in 1983. On pages 127-130, it discusses the fact that radiation error in weather shelters may be up to 3 degrees F., under full sun. Wang and Felton propose an alternate “weather shelter” comprised of two parallel plates that are white facing outside, and black facing inside.
A publication by S. Negri is titled, “Sensors May be Flawed,” published in The Arizona Republic, on Oct. 10, 1990. This article concerned installation of the HO83, which was an early artificially aspirated air temperature device. Now known as HO-1088, this device draws air across a temperature sensor. There are some questions as to its accuracy and the necessity of needing the fan during night time hours, which creates erroneous low temperature readings.
The Gill Plate Radiation Shield is another type of air temperature monitor. This multi-plate radiation shield is made from plastic, and it is susceptible to both direct and indirect radiation error. It requires natural airflow to abate higher temperatures that accrue from this being a passive device. Its product literature states a radiation error of 2.7 degrees F. RMS, with 2.2 mph airflow through the shield.
The technology described herein is referred to as a Radiation Compensated Thermometer, which uses the natural thermoelectric emissive characteristics of metal, because metal has more in common with the universe than plastic. This is also a step towards greater integration of sensor and shield.